Adding Bluetooth to existing Auto Guided Vehicle

I am new to the world of Arduino and am wondering about the feasibility or even ability to modify an existing manual control pendant on a auto guided forklift to Bluetooth control using an Arduino board. I see a lot of R/C cars being built or modified but they only require minor functionality ie for/rev, left/right, etc. I would be requiring almost 19 functions running through 16 connectors. I would like to use the existing hand unit only because of user familiarity. Attached is a picture of the hand unit. I would like to hear your thoughts.
Thank you.

Hi, I think you forgot to attach your hand unit picture, I hope it has enough buttons for having 19 combinations to dedicate each combination to your 19 function. Surely you can do this if your hand remote unit has bluetooth connectivity which can commute data wirelessly. Also, You will need a bluetooth module to connect it with arduino which can listen to the input from the hand unit via bluetooth.

Yes sorry the picture was too large. the hand unit is connected with a 16 wire cable, the wires have a habit of breaking, so I am trying to eliminate them. no Bluetooth on hand unit would have to build a transmitter and receiver for both machine and hand unit.

hand unit.jpg